Ophthalmoscope.



Vy@ .`O m. mf m n 5 L d S ua A, w .m n P K.L .w c D Rouw w VlMd m ELM w MA m .Hm W. BMM m* Bom ,C QV U www@ 0 MW N u HM f www m, e M 7 w M 0. M l 2 o u un N 70 (my C e lllnrrnn drames Parent trice@ EMIL B. MEYROWITZ, OF NEW YORK, N. Y., ASSIGNOR TO THE MEYROWI'IZ er MANUFACTURING COMPANY, A CORPORATION OF NE\V JERSEY.

ont-trnativtoscoet.

SPJEGIFIATXON forming part of Letters Patent No. 709,790; dated September 23, i902.

Application filed September 25, 1901. Serial No. 76,501. (No model) T (LEZ wwm "my 007%00772: On an axis o2, xed to the-back plate, is the Be it known that I, EMIL B. MEYROWITZ, a main lens-carrying disk B, having lenses l) citizen ot the United States, residing at the arranged in a circle near its periphery and city of New York, in the borough of Manhatadapted to be brought successively into line 55 tan and State ot New York, have invented with the opening o. These lenses are of -tcertainnew and usefulImprovementsin Ophand values, as usual, being arranged in a thalmoscopes, of which the followngisa full, graduated series, (indicated by the middle clear, and exact description. circle of figures shown on the face ofthe disk,)

This invention relates to ophthalmoscopes the lens-space opposite zero being vacant and 6o 1o designed for testing the focus of vision by the -tand values running in opposite dimeans of dioptric lenses. ret-.tions therefrom, the ligures of one set be The object of the invention is to produce ing white and of the other red or of any other an instrument which is cheap to construct, contrasting colors fordistinction. rlheinner simple in operation, and capable ot' giving a Acircle of figures indicate the values when the c5 ready indication ot' the value of the lenses in main lenses are successively combined with use at any given time. one of thesupplemeutal lenses, to be referred The invention embodies a main lens-carryto, and the outer circle gives the values ot ing disk adapted to be rotated by t'orce apcombinations with anothersupplementallens. plied to its periphery, a segment carrying Adjacent to its hub the disk carries a pin In', 7o zo supplemental lenses, each one of which is and around the edge of the disk is a [lange adapted to be used successively with all of b2, milled exteriorly, so that by pushing the lenses in the main disk, and a locking against the edge of the disk with the finger and unlocking device whereby the segment it can be rotated. y is held stationary whilethe main disk is mak- Mounted ou the hub of the main disk is a 75 z5 ing a complete rotation and is automatically segment C of such radius as to tit inside ot' released and allowed to rotate with the main the flange b2 and resting against the face of disk through the space of one lens at the end disk I5, with a tendency lo turn therewith by of each rotation of the main disk to thereby reason ot'ta certain friction-al engagement bebring a new supplemental lens into position tween them. 'lhis segment is provided with 8o 3o to cooperate with the main lexis and at the three lensopenings grouped together nearits same time disclose the figures of a new scale periphery.the middleopening c' being vacant ot' lens values correspoi'tding to the combinaand those on each side c2 and c havinglenses `tions to be made during the next rotation ot' of -tand values, each,as shown, being the main disk. teen. 'lheopeningsarein position tobeswung S5 rlhe invention will be described in detail into line with the lenses t) andthe opening d to with referenceto the accompanying d rawing atlord various combinations with the former. in which- The segment is furthermore provided with Figure l is a front view of my improved three openings c4, c5, and c6, located, respec ophthalmoscope. Fig. 2 is a rear view ot' the tively, over the three circles of liigures on 9o 4o same. Fig. 3 is an edge view. Fig. 4 is a disk B and spaced circular-ly the angular l'ace view of the main disk. Fig. 5 is a face distance between the lenses. Near the axis view of the segment, and Fig. (S is a view ot of the segment are formed three notches c7, the inner side of the guard-plate. corresponding in angular position with the The frame of the instrument consists of a openings c4, c5, and c The guard-plate or 95 back plate A and a front plate or guard d, mask o, is segmental in shape and is prothe two plates being parallel to each other vided with an elongated slot or notch @7,occuand separated only a sufiieient distance to pying a radial position and extending across accommodate the lens-carriers. The upper the three circles of figures on disk B. On its part of the back plate containsA a hole a', inner side the guard carries a pivoted pawl e, loo 5o through which thc eye of the operator is diadapted to engage the notches cT and be held rected. in such engagement by a spring e', also attached to the guard. -The end of the pawl is adapted to be struck on either side by the pin b and forced out of a notch. The pawl normally prevents the segment C from turning with disk B; but when the disk carries the piu h' against the pawl and removes it the frictional engagement between the disk and segment causes the latter to move with the former far enough to bring a new lensin the segment opposite the visual opening, whereupon the pin having been carried beyond the pawl allows the latter to fall into the next notch and again lock the segment. The segment then remains stationary during a complete rotation of the disk, during which time any number of lenses in the disk can be successively tried in combination with the particular lens in the segment. When the segment is thus shifted to bring a different supplemental lens into use, itis necessary to at the same time expose the new scale of Values, and this is done by the movement of the segment which brings a different opening c, c5, or cG into the slot a' and carries the one which was formerly exposed therein behind theguard-plate- WVhen the segment is in the mid-position, its vacant opening c is opposite the visual opening, and the opening c5 and middle scale are `then exposed andthe pawl is in the middle notch.- From this position the instrument can be turned in either direction.

Attached to the back of frame-plate A is a slide 't' of usual construction carrying a halfdiopter, which can be brought in front of the opening when needed. There is also the usual reecting-mirror I, having an opening at the center.

. It will be seen that this instrument can be operated without removing it from the eye to shift the supplemental lenses, as is necessary in some instruments, and the exposure of the scales` is accomplished without complex and delicate mechanism, such as pointers on the romeo exterior coperating with the supplemental lens-carrier on the inside. The instrument is therefore very serviceable and easily handled.

Having described my invention, I claim- 1. In an ophthalmoscope, the combination ot' a lens-disk, and a concentric supplemental lens-carrier, frictionally connected to rotate together, a frame supporting the disk and carrier, and a lock for the said carrier, preventing its rotation with the disk.

2. In an ophthalmoscopeVthe combination of a supporting-frame, a lens-disk, and a concentric supplemental lens-carrier,frictionally connected to rotate together and alock for the said carrier, preventing its rot-ation with the disk, and means for releasing and rengaging said lock at the end of each rotation of the disk.

In an ophthalmoscope, the combination of a supporting-frame, a lens-disk, and a concentric supplemental lens-carrier,frietionally connected to rotate together and a pawl pivoted to the frame normally engaging the carrier to prevent its rotation and means carried by the disk, for removing the pawl at the end ot' each rotation, substantially as described.

4. In an ophthalmoscope, the combination of a supporting-frame, a lens-disk, having a plurality of scales marked thereon, a concentric segment carrying supplemental lenses to which the scales correspond, openings in the segment respectively exposing the scales, a guard covering all of said Vopenings except one, a pawl pivoted to the frame adapted to hold the segment stationary andra-pin carried by the disk and adapted to remove the pawl.

In witness whereof I subscribe my signature in presence of two witnesses.

EMILv B. MEYROWITZ. Witnesses:

D. KUTTAs, J oHN F. LYNCH.

ssl 

